Discharge silencer for a hermetically encapsulated refrigerant compressor

ABSTRACT

The invention relates to a discharge silencer ( 6 ) for a hermetically encapsulated refrigerant compressor ( 1 ), which comprises a piston/cylinder unit ( 4 ) that compresses a refrigerant and has a compression chamber ( 3 ) and which is enclosed by a hermetically sealed compressor housing ( 2 ), wherein the compression chamber ( 3 ) is supplied with refrigerant coming from an evaporator through a suction silencer ( 5 ) and discharges refrigerant compressed by the piston/cylinder unit ( 4 ) into a pressure line ( 7   a, b ) through the discharge silencer ( 6 ). According to the invention, the discharge silencer ( 6 ) comprises a main body ( 8 ), on which an inlet flange ( 9 ) for the refrigerant coming from the piston/cylinder unit ( 4 ) is arranged, and an outlet channel ( 10 ), through which the refrigerant can be led into a pressure line ( 7   a, b ) that supplies a condenser with compressed refrigerant. The main body ( 8 ) has four side walls ( 11, 12, 13, 14 ), which each have a longitudinal extension and a width extension that is shorter than the longitudinal extension, wherein the two side walls ( 11, 12 ) having larger areas are opposite each other and are curved in the same direction when viewed in a direction parallel to the longitudinal extension.

FIELD OF THE INVENTION

The present invention relates to a discharge silencer for a hermetically encapsulated refrigerant compressor, which comprises a piston/cylinder unit that compresses a refrigerant and has a compression chamber, and is surrounded by a hermetically sealed compressor housing, wherein the compression chamber is supplied with refrigerant coming from an evaporator, by way of a suction silencer, and discharges compressed refrigerant compressed by the piston/cylinder unit, into a pressure line, by way of the discharge silencer.

STATE OF THE ART

The use of such discharge silencers in refrigerant compressor technology is sufficiently known and serves for reducing the noise emissions of the refrigerant compressor that occur during the discontinuous compression of refrigerant. Both metallic discharge silencers and nonmetallic variants are known. Depending on the placement and configuration of the discharge silencer, different frequency ranges can be silenced. Discharge silencers are characterized in that a chamber system is configured in the volume of a basic body, through which system compressed refrigerant must flow relatively shortly after its compression, in order to be able to achieve the desired silencing, on the one hand, but on the other hand also to be able to impede heat losses of the hot refrigerant after the compression process, in the discharge silencer, which has large surface areas as compared with the pressure line. In this connection, the configuration of the chamber system is based primarily on the frequency range to be silenced, but also on heat technology aspects.

The requirement of building the discharge silencer as close as possible to the outlet valve of the piston/cylinder unit, in order to achieve optimal silencing and minimal heat losses, is often connected with space problems in practice, and has led to the result that discharge silencers are often disposed to disruptively project from the cylinder head of the piston/cylinder unit into the interior of the compressor housing, which has effects, among other things, on the size of the compressor housing, which appears to bulge unnaturally at this location.

Within the course of an increase in resource efficiency and an accompanying reduction in the size of refrigerant compressors, as well as of their hermetically sealed compressor housings, however, it is desirable to accommodate the discharge silencer in the compressor housing in as space-saving a manner as possible.

PRESENTATION OF THE INVENTION

It is therefore the task of the present invention to provide a discharge silencer for a hermetically sealed refrigerant compressor, which takes up as little space as possible in the interior of the compressor housing.

According to the invention, this is achieved, in the case of a discharge silencer of the type mentioned initially, in that the discharge silencer has a basic body on which an inlet flange for the refrigerant coming from the piston/cylinder unit is disposed, and an outlet channel, by way of which the refrigerant can be transferred to a pressure line that supplies a condenser with compressed refrigerant, and which basic body has four side walls, each having a longitudinal expanse and a shorter width expanse, in comparison with the former, whereby the two side walls that have a greater surface area lie opposite one another and are configured to be curved, in the same direction, in each instance, when viewed in a viewing direction parallel to the longitudinal expanse.

The circumstance that the discharge silencer has two side walls that are curved in the same direction, in each instance, allows placement around a corner/edge or bend of the piston/cylinder unit and/or of components of the electric motor. Because of the two curvatures according to the invention, the discharge silencer can lie closely against the piston/cylinder unit or the electric motor with the one side wall, on the one hand, but also closely against the inside wall of the compressor housing, in order to consequently be able to also build the compressor housing as closely as possible to the piston/cylinder unit and to be able to minimize the empty space in the interior of the compressor housing.

According to a particularly preferred embodiment variant of the invention, it is provided that the curvature of the one side wall, which has a larger surface area, takes place constantly, preferably following the shape of an arc. Such an embodiment allows ideal adaptation of the discharge silencer to the usually cylindrical or dome-shaped wall of the compressor housing.

According to another preferred embodiment variant of the invention, it is provided that the curvature of the other side wall that is larger in surface area takes place discontinuously, in the form of at least two partial surfaces disposed at an angle relative to one another. The side wall of the discharge silencer can therefore be placed closely against an edge or bend of the electric motor (and/or components of it) and/or the piston/cylinder unit.

In order to achieve good silencing properties at a simultaneously compact construction of the discharge silencer, it is provided, according to another preferred embodiment variant, that the volume of the basic body is divided into different chambers, by means of multiple partitions that connect the two side walls.

Claim 5 relates to a hermetically encapsulated refrigerant compressor, having a piston/cylinder unit that compresses a refrigerant and has a compression chamber, and is driven by an electric motor, as well as a hermetically sealed compressor housing that surrounds this unit, whereby the compression chamber is supplied with a refrigerant coming from an evaporator, by way of a suction silencer, and discharges compressed refrigerant into a pressure line, by way of the discharge silencer, by means of the piston/cylinder unit. While achieving the advantages already described in the introduction, it is provided, according to the invention, that the discharge silencer surrounds and sheathes an edge or bend of the electric motor or a part of it and/or of the piston/cylinder unit, seen in the viewing direction of the edge or bend.

In a particularly spatially economical embodiment variant of the invention, the edge or bend is an edge of the stator sheet-metal package of the electric motor.

In a manner according to the invention, the discharge silencer comprises a basic body on which an inlet flange for the refrigerant coming from the piston/cylinder unit is disposed, and an outlet channel by way of which the refrigerant can be transferred to a pressure line that supplies a condenser with compressed refrigerant, and which basic body has four side walls, of which the two side walls that are larger in surface area and lie opposite one another are structured to be curved in the same direction, in each instance.

According to a preferred embodiment variant, the curvature of the one side wall that is larger in surface area takes place continuously, preferably following the shape of an arc.

According to another preferred embodiment variant, the curvature of the other side wall that is larger in surface area takes place discontinuously, i.e. approximately in the shape of at least two partial surfaces disposed at an angle relative to one another.

The discharge silencer is advantageously attached to the piston/cylinder unit in such a manner that the edge region formed between the at least two partial surfaces runs directly in front of and essentially parallel to the edge or bend of the electric motor and/or of the piston/cylinder unit. In this manner, a particularly space-saving arrangement of the discharge silencer within the compressor housing is made possible.

The space utilization within the compressor housing is further optimized in that, according to another preferred embodiment variant of the invention, it is provided that the curvature of one of the side walls that is larger in surface area corresponds, at least in certain sections, to the curvature of the compressor housing in the region of the placement of the discharge silencer within the compressor housing, seen in a viewing direction along the axis of the crankshaft of the electric motor.

BRIEF DESCRIPTION OF THE DRAWINGS

A brief description of the invention using figures of an exemplary embodiment now follows. These show:

FIG. 1 a schematic overall view of a hermetically encapsulated refrigerant compressor having a discharge silencer according to the invention (top view)

FIG. 2 a side view of the refrigerant compressor from FIG. 1, with the compressor housing partly in section

FIG. 3 an axonometric slanted view of a discharge silencer according to the invention

FIG. 4 a bottom view of a discharge silencer according to the invention

FIG. 5 a sectional view of the discharge silencer according to the invention

FIG. 6 another axonometric slanted view of the discharge silencer according to the invention

FIG. 7 a sectional view along line AA from FIG. 8

FIG. 8 a side view of a hermetically encapsulated refrigerant compressor, without the upper part of the compressor housing

FIG. 3 shows an axonometric slanted view of a discharge silencer 6 according to the invention, to be installed in a refrigerant compressor 1, having a basic body 8 and an inlet flange 9 for a refrigerant coming from the piston/cylinder unit 4 (see FIG. 1). The basic body 8 has an elongated shape and possesses four side walls 11, 12, 13, 14, each having a longitudinal expanse 33 and a width expanse that is shorter, in comparison with the former, which side walls, in a lower end region, are delimited by or make a transition into a floor section 28 that is essentially flat and runs orthogonal to the side walls 11, 12, 13, 14, which section can be configured as a separate component. In an upper end region, the side walls 11, 12, 13, 14 run out into the inlet flange 9. As can be seen in FIG. 3 and FIG. 6, in this connection, a cap-shaped ceiling section 29 is configured in the transition region between the side walls 11, 12, 13 and the inlet flange 9.

The hermetically encapsulated refrigerant compressor 1, as can be seen in FIG. 1 and FIG. 2, in which the discharge silencer 6 according to the invention is installed, is surrounded by a hermetically sealing compressor housing 2, the upper part of which is not shown in FIG. 1, whereby a piston/cylinder unit 4 driven by an electric motor 25 having a rotor 42 is disposed within the compressor housing 2. The piston/cylinder unit 4 comprises a piston 4 a that oscillates in a cylinder housing 4 b and compresses a refrigerant in a compression chamber 3, in known manner, and conveys it in the direction of the discharge silencer 6 according to the invention. Also evident in FIG. 1 are a crankshaft 26 that can rotate about an axis 27, having a crankshaft journal 26 a that is disposed eccentric to the axis 27, on which a connecting rod 30 that drives the piston 4 a is linked.

The refrigerant compressed in the compression chamber 3 is first drawn in from the compressor housing, which it reaches by way of a suction line 34 that comes from an evaporator that withdraws heat from a cooling chamber, by the piston 4 a, by way of a suction silencer 5.

In the floor section 28 of the discharge silencer 6, an outlet channel 10 is provided, by way of which the refrigerant can be transferred to a pressure line 7 a, b that supplies a condenser with compressed refrigerant.

As is particularly evident also in FIG. 4, which shows a view in the direction of the longitudinal expanse 33 of the discharge silencer 6, it is provided, according to the invention, that of the four side walls 11, 12, 13, 14 of the basic body 8, the two side walls 11 and 12, which have a larger surface area, lie opposite one another and are structured to be curved in the same direction, in each instance.

In this manner, it is possible that the discharge silencer 6 surrounds and sheathes an edge or bend 23 of the electric motor 25 or of parts of it and/or of the piston/cylinder unit 4 (see, in particular, FIG. 7). In the present exemplary embodiment, the edge or bend 23 sheathed by the discharge silencer 6 is an edge or bend 23 of a stator sheet-metal package 24 of the electric motor 25. In the following, for the sake of clarity, reference is made only to the concrete exemplary embodiment. However, it is clear to a person skilled in the art that the present invention relates very generally to a discharge silencer that can also sheathe and surround parts of the piston/cylinder unit, in addition or completely as an alternative.

What is meant with sheathe and surround according to the invention is that the sections of the discharge silencer 6 that run on the left and the right of the edge or bend 23 run as close as possible to the electric motor 25 or parts of it and/or to the piston/cylinder unit 4, in a viewing direction along the edge or bend 23, or, alternatively, that the side surface 12 of the discharge silencer 6 that faces the edge or bend 23 forms the negative counterpart to the contour of the electric motor 25 or parts of it and/or of the piston/cylinder unit 4, in the region of the edge or bend 23.

FIG. 7 shows the edge or bend 23 of the stator sheet-metal package 24 in detail. For the sake of clarity, in FIG. 7 the cylinder housing 4 b as well as parts of the electric motor 25 were cut away, as is evident from FIG. 8. In this connection, the outline edges 41 of the stator sheet-metal package 24 that run on the left and the right of the edge or bend 23, or, to state it more precisely, of the individual stator lamellae that are disposed to lie on top of one another, can once again have any desired shape, in other words can either be configured to run straight, as is shown in FIG. 7, on the left (solid line) and the right (broken line) of the edge or bend 23, or to have an irregular curvature, as is shown in FIG. 7 to the right of the edge of bend 23, with solid lines, depending on the requirements.

As is evident in FIG. 4, the curvature of the side wall 11 that faces away from the electric motor 25 or the piston/cylinder unit 4 runs continuously, preferably following the shape of an arc.

The side wall 12 that lies opposite the side wall 11, facing the electric motor 25 or the piston/cylinder unit 4, in contrast, can run discontinuously, for example as shown, in the form of at least two partial surfaces 12 a, 12 b that approximate a constant curvature and are disposed at an angle relative to one another. In other words, the side wall 12 has at least one kink or edge region 15 that divides the side wall 12 into at least two partial surfaces 12 a, 12 b.

The angle drawn in FIG. 4, measured between the outer surfaces of the partial surfaces 12 a, 12 b (facing the electric motor 25 or the piston/cylinder unit 4), is less than 180° and preferably greater than 90°. In the present exemplary embodiment, the angle between the partial surfaces 12 a and 12 b of the side wall 12 amounts to approx. 150°.

In the present exemplary embodiment, the discharge silencer 6 is attached to the piston/cylinder unit 4 in such a manner that the edge region 15 formed between the at least two partial surfaces 12 a, 12 b runs directly in front of the edge or bend 23 of the electric motor 25 or the piston/cylinder unit 4.

Furthermore, it can be provided that the curvature of the side wall 11 corresponds, at least in certain sections, to the curvature of the compressor housing 2, in the region of the placement of the discharge silencer 6 within the compressor housing 2, seen in a viewing direction long the axis 27 of the crankshaft 26 of the electric motor 25.

As is evident in FIG. 3, the opening of the inlet flange 9 of the discharge silencer 6 according to the invention possesses an essentially kidney-shaped cross-section, which, in the installed position, follows the cylinder housing 4 b of the piston/cylinder unit 4 shown in FIG. 1, or, to state it more precisely, a valve plate 35 that delimits the compression chamber 3 of the cylinder housing 4 b, whereby the opening cross-section of the inlet flange 9 encloses and seals one or more pressure openings present in the valve plate 35.

In a preferred embodiment variant, the inlet flange 9 of the suction silencer 6 is attached to the cylinder housing 4 b by means of one or more attachment elements 38, whereby the at least one attachment element 38 presses the inlet flange 9 against the cylinder housing 4 b in the axial direction of the piston bore. Such an arrangement is already disclosed in connection with the attachment of a cylinder head in EP 1888918 B1.

In the exemplary embodiment according to FIG. 1, the attachment element 38 is configured as a clamping element, which engages into the outer mantle of the cylinder housing 4 b, on corresponding undercuts 40, with three shank-shaped end regions 38 a, for example (see FIG. 2).

In a preferred embodiment variant of the invention, the basic body 8 of the discharge silencer 6 according to the invention extends from a region adjacent to the valve plate 35, in the direction of the electric motor 25 or in the direction of a floor region 39 of the compressor housing 2. The predominant part of the discharge silencer 6 is therefore disposed below the piston/cylinder unit 4, viewed in an operating position of the refrigerant compressor 1.

As can be seen in a sectional representation according to FIG. 5, the volume of the basic body 8 of the discharge silencer 6 is divided into different (in the present exemplary embodiment: five) chambers 19, 20, 21, 22, 36, by means of multiple partitions 16, 17, 18, 19 that connect the side walls 11, 12.

In this connection, the refrigerant indicated with arrows 31 a-c in FIG. 5 flows through all the chambers 19, 20, 21, 22, 36, before it is transferred out of the discharge silencer 6 to the pressure line 7 a, b, by way of the outlet channel 10.

As is evident in FIG. 5, the refrigerant that comes from the inlet flange 9 is divided into two refrigerant streams 31 a and 31 b that flow in the direction of the floor section 28, by means of a first partition 16; these streams combine again to form a refrigerant stream 31 c in a collection region 32 adjacent to the floor section 28, and enter into the third chamber 21. In this connection, the refrigerant stream 31 c is deflected by 180° and guided upward again, i.e. in a direction facing away from the floor section 28, before it is deflected by 180° once again in the region of the ceiling section 29 (of the third chamber 21) and conveyed, over its further course, into the pressure line 7 a, b, through the outlet channel 10. Analogous to the flow processes that take place in the third chamber 21, the refrigerant also flows through the fourth chamber 22 and the fifth chamber 36: Refrigerant streams 31 c′ and 31 c″ are guided from the floor section 28 to the ceiling section 29 and once again back to the floor section 28 (of the chambers 22, 36), before the refrigerant streams 31 c′ and 31 c″ leave the discharge silencer 6 through the outlet channel 10. In the outlet channel 10, all the refrigerant streams guided through the chambers 19, 20, 21, 22, and 36 therefore combine.

REFERENCE SYMBOL LIST

-   -   1 refrigerant compressor     -   2 compressor housing     -   3 compression chamber     -   4 piston/cylinder unit     -   4 a piston     -   4 b cylinder housing     -   5 suction silencer     -   6 discharge silencer     -   7 a, b pressure line     -   8 basic body of the discharge silencer     -   9 entry flange     -   10 outlet channel     -   11 side wall of the discharge silencer     -   12 side wall of the discharge silencer     -   12 a, 12 b partial surfaces of the side wall 12     -   13 side wall of the discharge silencer     -   14 side wall of the discharge silencer     -   15 edge on side wall 12     -   16 first partition     -   17 second partition     -   18 third partition     -   19 first chamber     -   20 second chamber     -   21 third chamber     -   22 fourth chamber     -   23 edge/bend of the electric motor     -   24 stator sheet-metal package     -   25 electric motor     -   26 crankshaft     -   27 axis of the crankshaft 26     -   28 floor section of the discharge silencer 6     -   29 ceiling section of the discharge silencer 6     -   30 connecting rod     -   31 a, 31 b, 31 c, 31 c′, 31 c″ refrigerant streams     -   32 collection region     -   33 longitudinal expanse of the side surfaces of the basic body     -   34 suction line     -   35 valve plate     -   36 fifth chamber     -   37 fourth partition     -   38 attachment element     -   39 floor region of the compressor housing 2     -   40 undercuts on cylinder housing 4 b     -   41 outline edges of the stator sheet-metal package or the stator         lamellae     -   42 rotor of the electric motor 

1-11. (canceled)
 12. Hermetically encapsulated refrigerant compressor (1), having a piston/cylinder unit (4) that compresses a refrigerant and has a compression chamber (3), and is driven by an electric motor (25), as well as a hermetically sealed compressor housing (2) that surrounds this unit, wherein the compression chamber (3) is supplied with a refrigerant coming from an evaporator, by way of a suction silencer (5), and discharges compressed refrigerant into a pressure line (7 a, b), by way of a discharge silencer (6), by means of the piston/cylinder unit (4), wherein the discharge silencer (6) surrounds and sheathes an edge or bend (23) of the electric motor (25) or a part of it and/or of the piston/cylinder unit (4), seen in the viewing direction of the edge or bend (23), wherein the discharge silencer (6) has a basic body (8) on which an inlet flange (9) for the refrigerant coming from the piston/cylinder unit (4) is disposed, and an outlet channel (10), by way of which the refrigerant can be transferred to a pressure line (7 a, b) that supplies a condenser with compressed refrigerant, and which basic body (8) has four side walls (11, 12, 13, 14), each having a longitudinal expanse and a shorter width expanse, in comparison with the former, wherein the two side walls (11, 12) that have a larger surface area lie opposite one another and are configured to be curved, in the same direction, in each instance, when viewed in a viewing direction parallel to the longitudinal expanse; wherein the curvature of the one of the side walls (12) that is larger in surface area takes place discontinuously, in the form of at least two partial surfaces (12 a, 12 b) disposed at an angle relative to one another; wherein the discharge silencer (6) is attached to the piston/cylinder unit (4) in such a manner that the edge (15) formed between the at least two partial surfaces (12 a, 12 b) runs directly in front of the edge or bend (23) of the electric motor (25)) and/or of the piston/cylinder unit (4); and wherein the curvature of the other of the side walls (11) that is larger in surface area corresponds, at least in certain sections, to the curvature of the compressor housing (2) in the region of the placement of the discharge silencer within the compressor housing (2), seen in a viewing direction along the axis (27) of the crankshaft (26) of the electric motor (25).
 13. Hermetically encapsulated refrigerant compressor (1) according to claim 12, wherein the edge or bend (23) is an edge of the stator sheet-metal package (24) of the electric motor (25).
 14. Hermetically encapsulated refrigerant compressor (1) according to claim 12, wherein the curvature of the other side wall (11) that is larger in surface area takes place continuously, preferably following the shape of an arc. 